Question: Jack's mother gave him $50$ chocolates to give to his friends at his birthday party. He gave $3$ chocolates to each of his friends and still had $2$ chocolates left. Write an equation to determine the number of friends $(x)$ at Jack's party. Find the number of friends at Jack's party.
Solution: Let $x$ be the number of friends at Jack's party. Jack gave $3$ chocolates to each of his $x$ friends, which is equal to $3x$. He also had $2$ chocolates leftover. Jack had a total of $3x+2$ chocolates. Since he had a total of $50$ chocolates, let's set this equal to $50$ : $ 3x+2=50$ Now, let's solve the equation to find the number of friends $(x)$ at Jack's party. $\begin{aligned} 3x+2&=50\\ \\ 3x+2{-2}&=50{-2}&&{\text{subtract }2} \text{ from each side}\\ \\ 3x&=48\\ \\ \dfrac{3x}{{3}}&=\dfrac{48}{{3}}&&\text{divide each side by ${3}$}\\ \\ \\ x&=16\end{aligned}$ The equation is $3x+2=50$. There were $16$ friends at Jack's party.